1 files changed, 51 insertions, 4 deletions

diff --git a/src/ir.cpp b/src/ir.cpp
index e22f96fba0..9b6cb8ab36 100644
--- a/src/ir.cpp
+++ b/src/ir.cpp
@@ -5826,12 +5826,26 @@ static bool ir_num_lit_fits_in_other_type(IrAnalyze *ira, IrInstruction *instruc
         {
             return true;
         }
-    } else if ((other_type->id == TypeTableEntryIdNumLitFloat &&
-                const_val->data.x_bignum.kind == BigNumKindFloat) ||
-               (other_type->id == TypeTableEntryIdNumLitInt &&
-                const_val->data.x_bignum.kind == BigNumKindInt))
+    } else if ((other_type->id == TypeTableEntryIdNumLitFloat && const_val->data.x_bignum.kind == BigNumKindFloat) ||
+               (other_type->id == TypeTableEntryIdNumLitInt   && const_val->data.x_bignum.kind == BigNumKindInt  ))
     {
         return true;
+    } else if (other_type->id == TypeTableEntryIdMaybe) {
+        TypeTableEntry *child_type = other_type->data.maybe.child_type;
+        if ((child_type->id == TypeTableEntryIdNumLitFloat && const_val->data.x_bignum.kind == BigNumKindFloat) ||
+            (child_type->id == TypeTableEntryIdNumLitInt   && const_val->data.x_bignum.kind == BigNumKindInt  ))
+        {
+            return true;
+        } else if (child_type->id == TypeTableEntryIdInt && const_val->data.x_bignum.kind == BigNumKindInt) {
+            if (bignum_fits_in_bits(&const_val->data.x_bignum,
+                        child_type->data.integral.bit_count,
+                        child_type->data.integral.is_signed))
+            {
+                return true;
+            }
+        } else if (child_type->id == TypeTableEntryIdFloat && const_val->data.x_bignum.kind == BigNumKindFloat) {
+            return true;
+        }
     }
 
     const char *num_lit_str = (const_val->data.x_bignum.kind == BigNumKindFloat) ? "float" : "integer";
@@ -5894,6 +5908,16 @@ static ImplicitCastMatchResult ir_types_match_with_implicit_cast(IrAnalyze *ira,
         return ImplicitCastMatchResultYes;
     }
 
+    // implicit conversion from T to %?T
+    if (expected_type->id == TypeTableEntryIdErrorUnion &&
+        expected_type->data.error.child_type->id == TypeTableEntryIdMaybe &&
+        ir_types_match_with_implicit_cast(ira,
+            expected_type->data.error.child_type->data.maybe.child_type,
+            actual_type, value))
+    {
+        return ImplicitCastMatchResultYes;
+    }
+
     // implicit widening conversion
     if (expected_type->id == TypeTableEntryIdInt &&
         actual_type->id == TypeTableEntryIdInt &&
@@ -7067,6 +7091,29 @@ static IrInstruction *ir_analyze_cast(IrAnalyze *ira, IrInstruction *source_inst
         return ir_analyze_err_wrap_code(ira, source_instr, value, wanted_type);
     }
 
+    // explicit cast from T to %?T
+    if (wanted_type->id == TypeTableEntryIdErrorUnion &&
+        wanted_type->data.error.child_type->id == TypeTableEntryIdMaybe &&
+        actual_type->id != TypeTableEntryIdMaybe)
+    {
+        TypeTableEntry *wanted_child_type = wanted_type->data.error.child_type->data.maybe.child_type;
+        if (types_match_const_cast_only(wanted_child_type, actual_type) ||
+            actual_type->id == TypeTableEntryIdNullLit ||
+            actual_type->id == TypeTableEntryIdNumLitInt ||
+            actual_type->id == TypeTableEntryIdNumLitFloat)
+        {
+            IrInstruction *cast1 = ir_analyze_cast(ira, source_instr, wanted_type->data.error.child_type, value);
+            if (type_is_invalid(cast1->value.type))
+                return ira->codegen->invalid_instruction;
+
+            IrInstruction *cast2 = ir_analyze_cast(ira, source_instr, wanted_type, cast1);
+            if (type_is_invalid(cast2->value.type))
+                return ira->codegen->invalid_instruction;
+
+            return cast2;
+        }
+    }
+
     // explicit cast from number literal to another type
     // explicit cast from number literal to &const integer
     if (actual_type->id == TypeTableEntryIdNumLitFloat ||